9_5 ECO Q A.pdf

1. What does physiological ecology generally refer to? Physiological Ecology: Study of how organisms adapt their physiology and anatomy to environmental variation. 2. What is microclimate and how does it differ from climate (or macroclimate)? Microclimate: Small-scale climate...

1. What does physiological ecology generally refer to? Physiological Ecology: Study of how organisms adapt their physiology and anatomy to environmental variation. 2. What is microclimate and how does it differ from climate (or macroclimate)? Microclimate: Small-scale climate variation (cm to km) over short periods; differs from macroclimate (large scale, long-term). 3. What factors influence microclimate? Be able to give examples. Factors Influencing Microclimate: Altitude (gray jay prefer higher, cooler altitudes) Aspect: In the Northern Hemisphere, south-facing slopes receive more direct solar radiation compared to north-facing slopes. This increased exposure to the sun results in higher temperatures on these slopes. Vegetation: such as trees and shrubs, can block or filter solar radiation, providing shade to the ground beneath and creating cooler, shaded areas. This shade reduces the amount of direct sunlight reaching the ground......Impact on Temperature Microclimate: By blocking solar radiation, vegetation can dramatically affect the temperature of a microclimate. The shaded areas under vegetation are typically cooler compared to areas exposed to direct sunlight, which helps moderate local temperatures and create a more favorable environment for certain plants and animals. ground color: The amount of energy absorbed by the ground is determined by the balance between incoming solar radiation and the amount reflected. Surfaces with high albedo (like snow) reflect more sunlight and absorb less, while surfaces with low albedo (like dark soil) absorb more sunlight and reflect less. Fresh snow has a high albedo (0.75 – 0.95), reflecting most of the incoming sunlight...Old snow has a slightly lower albedo (0.40 – 0.70)...Light dry soil has a moderate albedo (0.40), reflecting some of the sunlight...Dark dry soil has a low albedo (0.13), absorbing most of the sunlight. physical structures (e.g., burrows): Burrows provide insulation from extreme temperatures. The soil surrounding burrows acts as a buffer, protecting the animals from extreme temperature fluctuations that occur above ground. The temperature fluctuations in burrows are much less extreme compared to the air temperature  outside. For example, in the Chihuahuan Desert, New Mexico, air temperature fluctuated by 14°C, while the soil temperature at a depth of 22.5 cm only varied by 4°C. This moderated environment helps many desert animals avoid the extreme heat during the daytime. 4. Why does temperature matter for optimal organismal performance? Biochemistry and Enzymes: o Enzymes are proteins that catalyze biochemical reactions, and their activity is highly dependent on temperature. o The reaction rate of enzymes can increase significantly with temperature, by factors ranging from 10^7 to 10^14. o However, both low and high temperatures can impact the functionality of enzymes: ▪ Low temperatures slow down enzyme reaction rates. ▪ High temperatures can denature enzymes, altering their structure and rendering them inactive. Optimal Temperature Range: o Organisms perform best within a narrow temperature range where enzyme activity is optimized. o Temperature affects various biochemical reactions, enzyme function, and overall organismal performance. Impact on Organisms: o Organisms have evolved to thrive within specific temperature ranges that suit their biological processes. Deviations from these optimal ranges can impair growth, reproduction, and survival. Understanding these concepts highlights why temperature is a critical environmental factor that influences the fitness and functionality of all living organisms. 5. What are the main ideas behind the principal of allocation? Limited Energy Resources: All organisms have access to a finite amount of energy. Energy Allocation: This limited energy must be allocated among different functions necessary for survival and reproduction, such as: o Reproduction: Producing offspring. o Growth: Increasing in size or developing. o Maintenance (Defense): Sustaining basic biological functions and defending against environmental challenges. Trade-Offs: Allocating energy to one function (e.g., growth) reduces the energy available for other functions (e.g., reproduction or defense). This concept highlights the trade-offs organisms face in different environments. Thus, the principle explains that organisms cannot maximize all aspects of their fitness simultaneously due to the limitations imposed by available energy resources 6. What are the various ways organisms regulate their heat balance? Radiation: Gaining or losing heat through electromagnetic waves, such as sunlight. Convection: Heat transfer via moving air or water around the organism. Conduction: Direct heat transfer between two objects in contact, like an animal resting on a warm rock. Evaporation: Loss of heat through the conversion of water from liquid to vapor (e.g., sweating, panting). Metabolic Heat Production: Heat generated through metabolic processes within an organism. a. Which factors can increase or decrease (or both) heat balance? Radiation: Can increase or decrease heat depending on exposure to sunlight or shade. Convection: Can either cool or warm an organism depending on the surrounding air or water temperature. Conduction: Gains heat from warm surfaces or loses heat to cooler surfaces. Evaporation: Always decreases heat; effective cooling mechanism. Metabolic Heat Production: Generally increases heat due to energy expenditure. b. How do animals and plants differ in the main ways they use these mechanisms? Animals:  o Utilize active processes like sweating, panting, or shivering to maintain temperature. o Behavioral changes such as seeking shade, basking in the sun, or burrowing into the ground. o Use physical adaptations like fur, feathers, or specialized skin to manage heat transfer. Plants: o Use passive processes like transpiration (water loss from leaves) to cool down. o Adjust leaf orientation, size, and surface area to control heat absorption. o Regulate stomatal openings to manage water loss and heat dissipation. c. If I give an example of a type of behavior, be able to determine what type of heat balance mechanism it refers to (e.g., dog panting = evaporation). Dog Panting: Evaporation (cooling through moisture loss in breath). Lizard Basking: Radiation (absorbing solar energy to increase body temperature). Birds Soaring on Thermals: Convection (enhancing water movement around the body to cool down). Desert Plant with Small Leaves: Radiation/ Reducing heat absorption (minimizing the surface area exposed to the sun). Lizard running on hot surface using tip toes: conduction Metabolic Heat Production: shivering 7. What do poikilotherms, homeotherms, heterotherms, ectotherms, and endotherms refer to? Thermoregulation Types: 1. Poikilotherms:  o Definition: Organisms whose body temperature varies with the environmental temperature. They do not actively regulate their body temperature. o Examples: Most fish, amphibians, reptiles, and invertebrates. 2. Homeotherms: o Definition: Organisms that maintain a relatively constant internal body temperature, regardless of the environmental temperature. o Examples: Most mammals and birds. 3. Heterotherms: o Definition: Organisms that exhibit characteristics of both poikilotherms and homeotherms. They regulate their body temperature to some extent but may allow it to fluctuate with the environment during certain times, such as hibernation or daily torpor. o Examples: Some mammals (e.g., bats) and birds (e.g., hummingbirds). 4. Ectotherms: o Definition: Organisms that rely primarily on external heat sources to regulate their body temperature. o Examples: Reptiles, amphibians, fish, and most invertebrates. 5. Endotherms: o Definition: Organisms that produce heat internally through metabolic processes to maintain a constant body temperature. o Examples: Birds and mammals. a. Can organisms be a combination of the above -therms? Yes, some organisms can exhibit traits of more than one category. For example, heterotherms can show characteristics of both poikilotherms and homeotherms, depending on the environmental conditions or metabolic demands. Some animals might rely on external heat sources (like ectotherms) but also generate some metabolic heat (like endotherms) under specific conditions. b. If I were to give an example of an organism, say a plant or lizard, be able to identify which type of -therm(s) they are. Identifying -therms for Specific Organisms: Plant: Typically not classified in these categories but could be thought of as behaving like "ectotherms" since they rely on external temperatures.  Lizard: An ectotherm, as it relies on external sources of heat (e.g., basking in the sun) to regulate its body temperature. It is also a poikilotherm since its body temperature varies with the environmental temperature. 8. What does the thermoneutral zone represent? a. Be able to interpret plots of thermoneutral zones. b. Be able to identify the lower or upper critical temperatures in a thermoneutral zone plot. c. Given a thermoneutral zone plot, be able to identify temperatures where the organism will have to expend energy to maintain optimal body temperature. What does the thermoneutral zone represent? The thermoneutral zone (TNZ) represents the range of ambient temperatures where an organism can maintain its body temperature without needing to expend extra energy for heating or cooling. Within this range, the basal metabolic rate (BMR) is sufficient to sustain the organism's normal body temperature. a. Interpreting Plots of Thermoneutral Zones: On a plot showing the thermoneutral zone, the x-axis typically represents the ambient temperature (TaT_aTa ), while the y-axis represents the metabolic rate or energy expenditure. The TNZ is shown as the flat or stable portion of the metabolic rate curve, where the organism does not need to adjust its metabolism to maintain body temperature. Outside the TNZ, energy expenditure increases to either heat the body (below the lower critical temperature, TLCT_{LC}TLC ) or cool it down (above the upper critical temperature, TUCT_{UC}TUC ). b. Identifying Lower or Upper Critical Temperatures: Lower Critical Temperature (LCT or TLCT_{LC}TLC ): This is the point at the left end of the TNZ where the organism needs to start expending energy to warm itself, such as through shivering or increasing metabolic activity. Upper Critical Temperature (UCT or TUCT_{UC}TUC ): This is the point at the right end of the TNZ where the organism needs to expend energy to cool itself, such as through sweating or panting. c. Given a Thermoneutral Zone Plot, Identifying Temperatures Where Energy Expenditure Occurs: To determine where an organism will expend energy, look at the plot and identify the range of ambient temperatures outside the TNZ: o Below TLCT_{LC}TLC : Energy is expended for warming. o Above TUC : Energy is expended for cooling. The plot helps to pinpoint specific temperatures that trigger an increase in metabolic rate, indicating where the organism needs to adjust to maintain its optimal body temperature. 9. What are torpor, hibernation, and estivation, and how do they differ? Torpor, Hibernation, and Estivation: Torpor: o A state of reduced body temperature and metabolic rate that is typically short-term. o Used by animals to conserve energy when environmental conditions are unfavorable, such as during cold nights or periods of food scarcity. o Can occur daily (e.g., bats entering torpor at night). Hibernation: o A prolonged form of torpor lasting several days or months. o Allows animals to survive long periods of cold temperatures and reduced food availability. o Involves a significant drop in body temperature, metabolic rate, heart rate, and respiration. o Common in small mammals, like ground squirrels, and some species of bats. Estivation: o Similar to hibernation, but occurs during periods of extreme heat or drought. o Animals reduce metabolic rate and activity levels to conserve energy and water. o Common in amphibians, reptiles, and some mammals. Differences:  Duration: Torpor is short-term, hibernation is long-term, and estivation is seasonal during hot or dry conditions. Seasonality: Hibernation typically occurs in winter; estivation occurs in hot or dry conditions. Trigger: Torpor can be daily and is typically triggered by immediate environmental conditions (e.g., cold nights), while hibernation and estivation are responses to longer-term seasonal changes. 10.Because climate temperature regimes are changing across the planet, what are ways that organisms might respond? Responses to Climate Change: Distribution shifts (migration), phenology changes (breeding season/ flowers blooming), behavioral adaptations (inactivity periods), physiological adaptations (tolerance to differing temps), morphological adaptations (body size or coloration) 11.What are urban heat islands? Urban Heat Islands: Cities are warmer than surrounding areas due to human activities and structures. Notes: 1. The slide titled "Humboldt Current" explains the impact of the Humboldt Current on ocean conditions and climate. Currents and Upwelling:  a. The Humboldt Current is a cold ocean current that flows northward along the west coast of South America. It brings nutrient-rich deep waters to the surface, a process known as upwelling. b. Upwelling provides nutrients to the surface waters, supporting a high level of marine productivity, which is beneficial for local fisheries and marine life. Global Impact: c. The map shows various ocean currents, including the Humboldt Current, which is part of a global pattern of ocean circulation. These currents affect climate patterns, marine ecosystems, and biodiversity. The Humboldt Current significantly cools the air temperatures along the west coast of South America and impacts regional climate by creating cooler, drier conditions. It also contributes to one of the most productive marine ecosystems in the world due to nutrient upwelling. The unique ecological and geographical context of the Galapagos penguin, which thrives in an equatorial region due to the cooling effects of the Humboldt Current. 2. Adapting to one set of environmental conditions generally reduces a population’s fitness in other environments. Most species perform best in a fairly narrow range of temperatures 3. Phenology: refers to the study of the timing of seasonal biological events in the natural world. This includes observing and recording when specific events occur, such as flowers blooming, emergence of trees, migration of birds, breeding periods for animals